Air engine



Apnl 19 1927 J. M. DAPRoN AIRENGINE Fuga April 2711 1924 Patented Apr. 19, 1927.

UNITED PA l OFFICE,

JOSPH bariton, or sfr. L'o'UI's, nisse-Unir, nss'IGNoR To NATIONAL PNEUMATIC.

CMPANY,'F NEW YORK, fN. Y., A cenjeonATIoN 0F WEST VIRGINrA.

AIR ENGINE.

Application sied April i921, 1924. seriaiNmvoasrs.

M-y invention relates'to improvements in air engines of the doublescylinder type, wherein each cylinder is provided with a piston yand those pistons are connected by a single piston-rod; the .cylinder-head. of each of said cylinders having y,but a. single diametrical port. y

The Vpresent invention relates toa doublepfston air-engine .in which thel advancing l0 piston initially fmoves lagainst atmospheric pressure only .,(thecylindenspace before it having been exhausted of all .compression by being vented to atmosphere betere 4the advance stroke commences), and the valvestem being seated after the advance stroke has continued apredetermined distance (approximately haltl Ethe total length ofthe stroke in the .illustrated engine) closes the exhaust port; from lWhich `moment the continued advance of the .piston proceeds yto manufacture compressed air to serve as -a resistance cushion to check the movement ,of said advancing piston.

In the 'draWi-ngs- F ig. 1 is a longitudinal mid-"sectional view of an engine .embodying my invention.

Fig. 2 is an inverted vplan view ot .the

same.

Defscrigtz'on.

The opposed cylinders 3 and 4 are provided with the cylinder-heads 5 and 6 respectively, and are connected in alinement bythe central housing` 7 through which the shaft 8 is suitably journaled.

The pistons A and B are mounted in the cylinders 3 and 4 respectively and are mounted on the ends of the piston-rod C which serves to connect them rigidly together, and which midway its length is apertured at 9 to receive the roller 10 on the free end of the crank-arm 11.

Each of the cylinder-heads 5 and 6 has a central port 12, and each of the pistons A and B has a central bore 13 to receive a valve-stem 14 having a conoidal outer terminal 15.

The piston-rod C is provided With longitudinal bores 16, restricted at'17 to form a seat and bearing for the thimble 18, said thimble 18 receiving the inner end of the sleeve 19 in which the valve-stem 14 is yieldingly and adjustably mounted by means of the spring 20 and screiv plug 21.

The sleeve 19 Vhas at its base the shoulder 22 against which the coiled spring 23 mounted surrounding ysaid lsleeve 19 and with its inner terminal abutting against the mouth of the thi1nble'18.

The -roller l() is mounted bet-Ween the closed ends of ythe thimbles 18-18 asshoW in Fig. 1

lEach of the pistons A and B is lconstructed asillustrated'iu the sectional view of the .piston vkA in Fig. .1. The .outer face of the piston A is fprovided with the dished tvasher 24, surrounding the threaded nipple 25 and held in placeby the nut 2G. The inner tace 4of the .piston A is vprovided -Witliy a concentric Vdo'vetailed groove'27, in Which Vis imbedded an annulus-28 .of rubber or thelike, the func- `tion ,of which annulus A28 Iis .to impact upon the inner flange 290i the port 30, and-thereby seal the cylinder 3 at the lendv of the ',inivard stroke of the piston.A. AWhen the `cylinder 3is so sealed, the roller 10 will be cushioned between the closed .ends ot' the thimbles 12E-18, said thimbles 418--18 being balanced by the, pressure Within the cyliii'ders 3 and 4, t-he piston-rod C being` rigidly held by the Contact of the piston A With its flanged seat 29.'

-Zlloae of operation.

Compressed air is then admitted to the cylinder 3 through its port 12, driving the cylinders A and B to the right, until the terminal 15 ot the valve-stein 14 ot the piston B seats in and closes the port 12 ot' the cylinder 4. The rapidity ot the movement thus far described will correspond with the pressure of the air introduced to the cylinder 3, and that speed Vmust be diminished by an opposing pressure in the cylinder 4, Which is built up in the further progress toward the end of its outward stroke of the piston B by the cooperation of the valve-stem 14 and the thimble 18 (due to their respective spring-mountings above described), with the roller 10.

The described mechanism may be varied in construction in many respects, as it is merely the single form exhibited by me in response to the statutory requirement|` without departing' 'from my invention es delined in the Yfollowingclaims.

In the inode of operation of the engine oi my invention, however, euch o'l' the double cylinders must he provided with a. port 12. or its equivalent, in its outer hend through which the cylinder muy loe readily und quicio ly exhnusted to atmosphere; und the inner heed il ot euch cylinder must have n relutively .large port 3l), or its equivalent. to :idmit nir at atmospheric pressure treely into its communiinting cylinder nt ull times sure when that linder is sealed hy the contact ol' the inner lnce of the piston (A, or l) with the inner mouth of snid port Si).

I claiml. In :Ln nir engine in combination, two nlined cylinders; a central housingconnectinel seid cylinders; n` pair ot pistons mounted one in earch of seid cylinders; a piston-rod Connecting said pistons; tiro cylinder-heads. one mounted on the outer end ot erich of seid cylinders. and each having :i central port; a restricted longitudinal here in euch end of seid piston-rod; n thimhle seated in the inner end of each of said hores; u crank jonrnnled in said housing;` having :i roller thereon, said roller projecting` between said thimbles: e sleeve mounted in euch of said bores :1nd yieldingrly und slidubly mounted Within one of seid thimhles; and n velvestem yieldingly mounted in each o'l said sleeves, each vulve stem being adapted to sent in the port on the cylinder head of the cylinder in which it moves hei'ore the completion of the stroke of the piston on which it is mounted.

2. In fin air engine in combination, two :dined cylinders; e central housing connectingr seid cylinders; n puir ot pistons mounted one in erich olf seid cylinders; n pietourod connecting said pistons; tvvo cylinder-hends` one mounted. on the outer end ot each of seid cylinders, und euch having; u central port: :i restricted longitudinal here. in each end oi. seid piston-rod; n thimhle seated in the inner end ot' each ot .seid hores; e crank journnlciil in seid housing having nv roller thereon, seid roller ilirojccting between Suid thimhles; a sleeve mounted in euch o'll Said hores and yieldingrly :ind sliduhly mounted Within one ot seid thiuihles: und ni vulvestem huring n. conoidel outer terminal :irrnugcd to he sented in the port oi the udincent cylinder heed und vieli'lingly mounted in each ot seid sleeree.

3. In in nir engine in comliinntiont tivo ulined cylinders; :i ceutrul housing' connecting seid cylinders; n pri/ir oi pistons mounted one in euch of said cylinders; zi. piston-rod connectinnr said pistons; tivo cylimler-hezide, one mounted on the outer end oil: euch of seid cylinders. end each having :i central port: n restricted lonz-ritudinnl bore in each end oi? seid piston-rod; e thimhle sented in the inner end of euch ot seid hores; n sleeve mounted in eech of seid. bores and vieldingly und elidnhly mounted within one ot seid thimhles; n vulve-stem yieldingly mounted in each oll said sleeves; e crunk nrm mounted in seid housing; und :i roller carried thereby, .said roller beine; mounted hetiveen the inner ends of said thimhles, euch valve stem heine* adapted to sent in the port on the cylinder head o'li the cylinder in which it moves hefore the completion of the Stroke olf the pifton on which it is mounted In testimony whereof I have hereunto attixed my signature.

JOSEPH M. DAPRON. 

